MS 5 EX => CSP? License doesn't work in CSP

I have a MS5 EX license (two, actually, on DVD) that for one reason or another were never registered w/ Smith Micro. I'm running 5.0.3 on Mac OS 10.12.6. I'm under the impression that MS 5 EX can be updated directly to CSP 1.x.

Two questions:

1.) Should the MS5 EX license work out of the box w/ CSP? I've tried installing CSP 1.5 and CSP 1.6.4 "update" from the Celsys site, and the serials are not recognized by either.

2.) What was the last MS 5 EX update? I want to see if I can get that from SM... though I won't be holding my breath...

@kbaccki and of course, they're right next to each other on the keyboard. Don't kick yourself over that one. I can't count the number of times working in IT support I had to explain to people that holding down the shift key while pressing the semi-colon key will not enter their correct password, since it contains a semi-colon, not a colon. D'Oh! (Quite apart from the fact that they were still using the default admin password D-8<).